--- a/packages/net/lwip_tcpip/current/include/netif/etharp.h
+++ b/packages/net/lwip_tcpip/current/include/netif/etharp.h
@@ -35,21 +35,33 @@
 #ifndef __NETIF_ETHARP_H__
 #define __NETIF_ETHARP_H__
 
-#ifndef ETH_PAD_SIZE
-#define ETH_PAD_SIZE 0
-#endif
+#include "lwip/opt.h"
+
+#if LWIP_ARP /* don't build if not configured for use in lwipopts.h */
 
 #include "lwip/pbuf.h"
 #include "lwip/ip_addr.h"
 #include "lwip/netif.h"
 #include "lwip/ip.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef ETH_PAD_SIZE
+#define ETH_PAD_SIZE          0
+#endif
+
+#ifndef ETHARP_HWADDR_LEN
+#define ETHARP_HWADDR_LEN     6
+#endif
+
 #ifdef PACK_STRUCT_USE_INCLUDES
 #  include "arch/bpstruct.h"
 #endif
 PACK_STRUCT_BEGIN
 struct eth_addr {
-  PACK_STRUCT_FIELD(u8_t addr[6]);
+  PACK_STRUCT_FIELD(u8_t addr[ETHARP_HWADDR_LEN]);
 } PACK_STRUCT_STRUCT;
 PACK_STRUCT_END
 #ifdef PACK_STRUCT_USE_INCLUDES
@@ -73,13 +85,34 @@ PACK_STRUCT_END
 #  include "arch/epstruct.h"
 #endif
 
+#define SIZEOF_ETH_HDR (14 + ETH_PAD_SIZE)
+
+#if ETHARP_SUPPORT_VLAN
+
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct eth_vlan_hdr {
+  PACK_STRUCT_FIELD(u16_t tpid);
+  PACK_STRUCT_FIELD(u16_t prio_vid);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#define SIZEOF_VLAN_HDR 4
+#define VLAN_ID(vlan_hdr) (htons((vlan_hdr)->prio_vid) & 0xFFF)
+
+#endif /* ETHARP_SUPPORT_VLAN */
+
 #ifdef PACK_STRUCT_USE_INCLUDES
 #  include "arch/bpstruct.h"
 #endif
 PACK_STRUCT_BEGIN
 /** the ARP message */
 struct etharp_hdr {
-  PACK_STRUCT_FIELD(struct eth_hdr ethhdr);
   PACK_STRUCT_FIELD(u16_t hwtype);
   PACK_STRUCT_FIELD(u16_t proto);
   PACK_STRUCT_FIELD(u16_t _hwlen_protolen);
@@ -94,33 +127,66 @@ PACK_STRUCT_END
 #  include "arch/epstruct.h"
 #endif
 
-#ifdef PACK_STRUCT_USE_INCLUDES
-#  include "arch/bpstruct.h"
-#endif
-PACK_STRUCT_BEGIN
-struct ethip_hdr {
-  PACK_STRUCT_FIELD(struct eth_hdr eth);
-  PACK_STRUCT_FIELD(struct ip_hdr ip);
-} PACK_STRUCT_STRUCT;
-PACK_STRUCT_END
-#ifdef PACK_STRUCT_USE_INCLUDES
-#  include "arch/epstruct.h"
-#endif
+#define SIZEOF_ETHARP_HDR 28
+#define SIZEOF_ETHARP_PACKET (SIZEOF_ETH_HDR + SIZEOF_ETHARP_HDR)
 
 /** 5 seconds period */
 #define ARP_TMR_INTERVAL 5000
 
-#define ETHTYPE_ARP 0x0806
-#define ETHTYPE_IP  0x0800
+#define ETHTYPE_ARP       0x0806
+#define ETHTYPE_IP        0x0800
+#define ETHTYPE_VLAN      0x8100
+#define ETHTYPE_PPPOEDISC 0x8863  /* PPP Over Ethernet Discovery Stage */
+#define ETHTYPE_PPPOE     0x8864  /* PPP Over Ethernet Session Stage */
+
+/** ARP message types (opcodes) */
+#define ARP_REQUEST 1
+#define ARP_REPLY   2
 
-void etharp_init(void);
+#if ARP_QUEUEING
+/** struct for queueing outgoing packets for unknown address
+  * defined here to be accessed by memp.h
+  */
+struct etharp_q_entry {
+  struct etharp_q_entry *next;
+  struct pbuf *p;
+};
+#endif /* ARP_QUEUEING */
+
+#define etharp_init() /* Compatibility define, not init needed. */
 void etharp_tmr(void);
+s8_t etharp_find_addr(struct netif *netif, struct ip_addr *ipaddr,
+         struct eth_addr **eth_ret, struct ip_addr **ip_ret);
 void etharp_ip_input(struct netif *netif, struct pbuf *p);
 void etharp_arp_input(struct netif *netif, struct eth_addr *ethaddr,
          struct pbuf *p);
-err_t etharp_output(struct netif *netif, struct ip_addr *ipaddr,
-         struct pbuf *q);
+err_t etharp_output(struct netif *netif, struct pbuf *q, struct ip_addr *ipaddr);
 err_t etharp_query(struct netif *netif, struct ip_addr *ipaddr, struct pbuf *q);
 err_t etharp_request(struct netif *netif, struct ip_addr *ipaddr);
+/** For Ethernet network interfaces, we might want to send "gratuitous ARP";
+ *  this is an ARP packet sent by a node in order to spontaneously cause other
+ *  nodes to update an entry in their ARP cache.
+ *  From RFC 3220 "IP Mobility Support for IPv4" section 4.6. */
+#define etharp_gratuitous(netif) etharp_request((netif), &(netif)->ip_addr)
+
+err_t ethernet_input(struct pbuf *p, struct netif *netif);
+
+#if LWIP_AUTOIP
+err_t etharp_raw(struct netif *netif, const struct eth_addr *ethsrc_addr,
+                 const struct eth_addr *ethdst_addr,
+                 const struct eth_addr *hwsrc_addr, const struct ip_addr *ipsrc_addr,
+                 const struct eth_addr *hwdst_addr, const struct ip_addr *ipdst_addr,
+                 const u16_t opcode);
+#endif /* LWIP_AUTOIP */
+
+#define eth_addr_cmp(addr1, addr2) (memcmp((addr1)->addr, (addr2)->addr, ETHARP_HWADDR_LEN) == 0)
+
+extern const struct eth_addr ethbroadcast, ethzero;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LWIP_ARP */
 
 #endif /* __NETIF_ARP_H__ */